1. Technical Field
The present invention relates to automotive wheel alignment and, more particularly, to an alignment head for use with wheel alignment systems.
2. Description of the Related Art
Automotive wheel alignment heads mount to the wheels of an automobile for determination of wheel alignment. These alignment heads are pervasive in automobile repair facilities. Modern automotive wheel alignment heads are complex and include numerous parts that must be assembled into one unit. Such systems, however, require longer assembly times and are subject to increased costs. FIGS. 7A and 7B are perspective views of a conventional alignment head 300. The alignment head 300 includes a main body 310 that is used to house a track toe sensor (not shown). A cover 312 is disposed over the main body 310. A tube 314 is coupled at one end to the main body 310, and extends therefrom. A cross toe sensor module 316 is mounted on the opposite end of the tube 314. The cross toe sensor module 316 houses a cross toe sensor (not shown). A second cover 318 is provided to cover the cross toe sensor module 316 and the cross toe sensor.
Conventional alignment heads 300, such as the one illustrated in FIGS. 7A and 7B, suffer from various drawbacks. For example, the numerous components must be assembled using conventional fasteners or other connection methods. The components also must be assembled with substantial precision. In order to properly align the wheels of a vehicle, it is crucial that all the components remain in their designated orientations. During normal operations, however, it is common for alignment heads to fall or otherwise experience impacts that cause these components to deviate from their designated orientations. Consequently, the vehicle wheels cannot be properly aligned until the alignment head is repaired to its original specification.
The components must also be manufactured to close tolerances in order to allow control software to compensate for discrepancies. For example, the main body 310 and other components can be manufactured using various processes such as sand casting and die casting. These components must then be subjected to numerous machining operations in order to achieve the tolerances required to perform proper wheel alignment and calibration of the alignment head 300. These operations significantly increase the manufacturing cost of the alignment head 300.
Conventional alignment heads 300 also require systems for calibrating (i.e., leveling) the alignment head 300. Typically, a plurality of steel, or lead, weights are disposed within the alignment head 300. When components are moved from their designated orientations, the alignment head 300 must be recalibrated. This requires that weights be added or removed to relevel the alignment head 300. Recalibration of the alignment head 300 can be difficult and time consuming because the alignment head 300 must be disassembled and weights of appropriate mass must be selected and installed to level the alignment head 300.
Another problem associated with conventional alignment heads 300 is the manner in which the alignment head 300 is locked when a caster sweep must be performed. Specifically, conventional alignment heads 300 utilize a locking knob 320 that engages a central shaft of the alignment head 300 downwardly from the top portion of the alignment head 300. This can result in camber shift during the alignment process.
Accordingly, there exists a need for an alignment head having internal components that cannot be moved easily from their designated orientations. There also exits a need for an alignment head that can be manufactured cost-effectively. There exists a further need for an alignment head that can be easily leveled once attached to the wheel of a vehicle.
An advantage of the present invention is the ability to provide an alignment head having internal components mounted such that they cannot be easily moved from their designated orientations as a result of impact or repeated use. Another advantage of the present invention is an alignment head that does not require high-precision machining operations to construct, hence reducing the overall manufacturing cost. Yet another advantage of the present invention is an alignment head that can be easily leveled and calibrated once attached to the wheel of a vehicle.
These and other problems are addressed by the present invention wherein an alignment head includes a two piece housing within which sensors and transceivers are disposed.
According to one aspect of the present invention, an alignment head comprises a housing, a frame assembly, at least one sensor, a pair of transceivers, and control circuitry disposed therein. The housing is in the form of a left and right cover that are adapted for engagement with each other. Additionally, the housing has a front portion, a rear portion, and a central portion. The frame assembly is positioned within the central portion of the housing, and the sensor is mounted on the frame assembly. The first transceiver is positioned within the front portion of the housing, while the second transceiver is positioned within the rear portion of the housing. The sensor is used to generate data indicative of the orientation of the alignment head. The first and second transceivers are used to transmit and receive alignment signals. The control circuitry receives data from the sensors and alignment signals from the first and second transceivers. The control circuitry utilizes this information to generate alignment information that can be used to align the wheels of the vehicle. According to such an arrangement, all the components of the alignment head can be internally disposed within one housing. Further, the housing is constructed with sufficient rigidity to withstand impacts without disturbing the orientation of the internal components.
According to another aspect of the present invention, a subassembly is provided within the rear portion of the housing for storing a power supply unit. The power supply unit can be in the form of conventional circuitry for receiving either direct current (DC) or alternating current (AC) from an external source. Alternatively, the power supply unit can be in the form of either rechargeable or conventional batteries. Such an arrangement provides a technician with flexibility in selecting locations wherein wheel alignments can be performed.
According to another aspect of the present invention, the frame assembly includes a pair of skeletal plates respectively positioned within the left and right covers of the housing. An extrusion member having a passage therethrough is positioned between the two skeletal plates. Additionally, a shaft is positioned within the passage and extends from the left cover to the right cover of the housing. According to such an arrangement, the housing is structurally reinforced, and the sensor can be efficiently positioned.
Additional advantages and novel features of the present invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the present invention. The embodiments shown and described provide an illustration of the best mode contemplated for carrying out the present invention. The invention is capable of modifications in various obvious respects, all without departing from the spirit and scope thereof. Accordingly, the drawings and description are to be regarded as illustrative in nature, and not as restrictive. The advantages of the present invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.